The leading theory explaining long gamma ray bursts such as GRB 130427A posits that they are created during the most energetic explosions in the cosmos, which occur when a very massive star collapses on itself. When the core of a massive star collapses, it can eject a jet of gas into space at nearly the speed of light. Collisions between the fast-moving gas and its surroundings, as well as within the jet itself, create gamma rays. This NASA-Goddard animation depicts the cosmic event that culminated in GRB 130427A.
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